Adjustable cam control system for a sheet-handling apparatus



c. 1.. LARspN Dec. 10, 1968 ADJUSTABLE CAM CONTROL SYSTEM FOR ASHEET-HANDLING APPARATUS Filed Oct. 6, 1967 3 Sheets-Sheet 1 Dec. 10,1968 c. L. LARSON 3,415,391

ADJUSTABLE CAM CONTROL SYSTEM FOR A SHEET-HANDLING APPARATUS Filed Oct.6, 1967 3 Sheets-Sheet 2 250i if 246 Charles L. Larson 6 BY I'NVENTOR#41114 $444M Dec. 10, 1968 LARSON 3,415,391

ADJUSTABLE CAM CONTROL SYSTEM FOR A SHEET-HANDLING APPARATUS "1 Fl edOct 6 1967 5 Sheets-Sheet 5 58 i "i 12/4 206 "1 "Im 1], "'l] r. 98 i /28208 & E1 1 o o H O O O /98 O all Char] es L. Larsen INVENTOR UnitedStates Patent 3,415,391 ADJUSTABLE CAM CONTRGL SYSTEM FUR ASHEET-HANDLING APPARATUS Charles L. Larson, Grants Pass, Greg, assignorto Jeddeloh Bros. Sweed Mills, ind, Gold Hiii, Greg,

a corporation of Oregon Filed Get. 6, 1967, Ser. No. 673,445 5 Claims.(Cl. fi l-16.4)

ABSTRACT OF THE DISCLOSURE Sheet-handling apparatus including amultideck dryer, a feeder for feeding during a feed cycle successivecharges of veneer sheets onto the infeed ends of dilferent decks in thedryer, and an unloader including an intermittently-operated,motor-driven discharging mechanism for each dryer deck, operable totransfer sheets away from the offbearing end of the deck. Cam mech anismis provided which is positively driven by the feeder for rotationthrough a given angular distance during each feed cycle. The cammechanism, during rotation, engages and actuates successive switcheswhich, in turn, effect operation of different discharging mechanisms inthe unloader. The cam mechanism is adjustable to vary the length of timethat it engages a switch, thus to vary the duration of the operatingperiods of the discharging mechanisms.

This invention relates to sheet-handling apparatus, and, moreparticularly, to such apparatus which includes means for unloadingcharges of sheets from the offbearing ends of the different decks in amultiple-deck conveyor. A preferred embodiment of the invention isdescribed herein in connection with a multiple-deck dryer for dryingsheets of wood veneer.

A conventional veneer dryer includes multiple stacked conveyor deckswhich are power-driven (normally from a common drive means) to transportsheets through a chamber in the dryer where the sheets are heated anddried. Typically, green (or wet) sheets of veneer are fed, recurrently,in successive charges onto the infeed ends of different docks in a dryerby means of a feeder, such as the one described in US. Reissue Patent24,843, issued July 12, 1960, entitled Sheet Loading Mechanism forMultideck Conveyor. More specifically, such a feeder includes a loadingconveyor mechanism which, during a feed cycle of the feeder, operates totransfer a charge of sheets onto each deck in the dryer. Properpositioning of the loading conveyor mechanism prior to transfer of acharge to a deck results from the action thereon of a rotating cam inthe feeder that revolves once during each feed cycle.

Dried sheets may be transferred away from the olfbearing ends of thedryers decks by means of an unloader adapted to receive successivecharges of sheets emerging from the dryer. The unloader includes areceiving station for each deck positioned adjacent the olfbearing endthereof to receive and collect charges of sheets coming from the deck.lntermittently-operated discharging mechanism in the unloader may beoperated to discharge sheets from the station, thereby clearing thestation so that it may receive another charge. Sheets discharged fromthe unloader may then be carried away on an oifbearing conveyor, orthrough other means, for grading and sorting, or for further processing.

For an unloader to operate without constant supervision some means mustbe provided for controlling the operating periods of the variousdischarging mechanisms in the unloader, whereby automatically, and afterreceiving a charge of sheets, the respective receiving stations in theunloader are cleared promptly to prepare them for 3,415,391 PatentedDec. 10, 1968 receiving other charges. Bottoming this invention is theconcept of controlling the unloader operation through means positivelycoupled to movement of the feeder for the dryer, organized so that foreach charge fed the dryer, another charge is unloaded in the unloader.The invention also features novel means for adjusting the timed relationof the operation of the unloader mechanisms with respect to movements inthe feeder, so that the amount of time selected between the feeding of acharge and the unloading of a charge may be changed to take care ofvariable conditions such as the handling of different sheet lengths,etc. A specific feature of the invention is the provision of novel meansenabling ready adjustment of the length of time that a given dischargingmechanism will operate, and the making of such an adjustment whileavoiding such a contingency as two discharging mechanisms operatingsimultaneously, which could cause considerable disarray of sheets on anymeans that collects the sheets discharged from the unloader.

Thus, a general object of the present invention is to provide, in asheet-handling organization of the type outlined, novel means forcontrolling the operation of a sheet unloader which itself is controlledby movement of the feeder.

More particularly, an object of the invention is to provide, insheet-handling apparatus comprising a multideck conveyor, a feeder forfeeding successive charges of sheets sequentially to the infeed ends ofdifferent decks in the conveyor, and an unloader having a receivingstation for each deck, novel means for controlling both the time atwhich unloading of a receiving station is performed and the duration ofthe unloading operation.

More specifically, an object is to provide, in apparatus of the typedescribed wherein the feeder includes an element that revolves through agiven angular distance during each feed cycle, noval rotating cammechanism operatively connected to and positively driven by the element,such cam mechanism, by virtue of its connection to the element, alsorevolving through a given angular distance during each feed cycle. Thecam mechanism, while revolving, effects operation of successivedischarging mechanisms in the unloader.

According to the invention, a switch or control device is provided toreach discharging mechanism, operatively connected to a drive motor inthe mechanism. The switch has a nonactuating state that it normallyoccupies, and an actuating state that it may be placed in to effectoperation of its associated drive motor. The various switches arepositioned adjacent the cam mechanism mentioned above, and withrevolving of the cam mechanism, are engaged thereby and placedsuccessively'in their actuating states. The relative positions of theswitches and cam mechanism may be adjusted to establish an appropriatetimed relationship between the initiation of a feeding operation andthat of a discharging or unloading operation.

An important part of the invention is the provision of novel cammechanism of the type described which is readily adjusted to vary thelength of time that it engages a particular switch to place it in itsactuating state, thus to vary the operating period of the associateddischarging mechanism.

These and other objects and advantages attained by the invention willbecome more fully apparent as the description which follows is read inconjunction with the accompanying drawings, wherein:

FIG. 1 is a simplified side elevation illustrating various units ofsheet-handling apparatus including a multideck veneer dryer, a feederfor feeding sheets of veneer into the infeed end of the dryer, and anunloader constructed and operated according to the present invention fortransferring sheets away from the olfbearing end of the dryer;

FIG. 2 (second sheet of the drawings) is a view on a larger scale thanFIG. 1, illustrating novel cam mechanism constructed according to theinvention driven by the feeder in FIG. 1;

FIG. 3 is a cross-section view, taken generally along the line 33 inFIG. 2;

FIG. 4 (third sheet of the drawings) is a side elevational view, also ona larger scale than FIG. 1, illustrating details of construction of theunloader in FIG. 1;

FIG. 5 (first sheet of the drawings) is a fragmentary cross-sectionalview taken generally along the line 5-5 in FIG. 4; and

FIG. 6 (second sheet of the drawings) is a schematic diagramillustrating an electrical circuit connecting switches actuated by thecam mechanism of FIGS. 2 and 3 and discharging mechanisms employed inthe unloader.

Turning now to the drawings, and referring first to FIG. 1, indicatedgenerally at It is a conventional veneer dryer having an infeed end 10aand a discharge or offbearing end 1012. The dryer shown includes amultipledeck conveyor having five decks stacked one above the otherindicated generally at 12, 14, 16, 18, 20. Each deck takes the form of aseries of paired rolls (for simplicity, many of the rolls are not shownin FIG. 1) such as rolls 22 for deck 14. The rolls extend transverselyof the dryer, and the pairs of rolls follow one another along the lengthof the dryer. The rolls in the various decks are suitably drivinglyconnected for simultaneous rotation to a common sprocket 24, and withturning of this sprocket, rotate to move veneer sheets through thedryer. The rolls in all of the decks turn at substantially the samespeed. Sprocket 24 is driven by an electric motor 26 which is connectedto the sprocket by a chain 28.

Aprons 12a, 14a, 16a, 18a and 20a indicated for reasons of simplicity asdashed lines in FIG. 1 comprise roll conveyors leading to the variousdecks in the dryer.

Positioned adjacent the infeed end of dryer 10 is a feeder whichoperates in a feed cycle to feed successive changes of veneer sheetsonto the infeed ends of different decks in the dryer. The feederincludes a frame 32, and a loading conveyor mechanism shown in dashdotoutline at 34 pivoted on the frame at 36 for swinging about a horizontalaxis extending transversely of frame 32. In general terms, the loadingconveyor mechanism feeds veneer sheets along a plane indicated indash-dot outline at 38 which, with swinging of the mechanism, is movedinto registry with the infeed ends of the aprons for the decks in thedryer. In FIG. 1, mechanism 34 has been swung to register plane 38 withthe infeed end of apron 14a for deck 14.

During each feed cycle of feeder 30, the loading conveyor mechanism isswung into appropriate alignment with each of the different decks in thedryer by means such as a large cam mechanism (not shown) secured to ashaft 40 suitably journaled on frame 32. The cam engages the undersideof the loading conveyor, and is constructed so that on being rotated byrotation of shaft 40, the loading conveyor swings on pivot 36 with itsforward end swinging past the infeed ends of the aprons while dwellingfor a short time on moving into registry with a particular apron. In theunloader shown a single revolution of shaft 40 in the directionindicated by the arrow, defines a feed cycle for the feeder, and in sucha cycle, unloading conveyor mechanism 34 progresses from deck 20upwardly to deck 12, and then back to deck 20.

Also secured to shaft 44 is a disc 42 having five finger elements, suchas elements 44, projecting axially to one side of the disc, with thenumber of elements corresponding to the number of decks in dryer 10. Thefinger elements are positioned to actuate a switch 46 as the elementsrotate with the disc and shaft 40. Switch 46, upon being actuated by afinger elements, causes means such as pinch rolls (not shown) providedin mechanism 34 to come together and feed a charge of sheets to a deckin the dryer.

Shaft 40 is rotated under power by means of a pair of chains 48, 50which connect the shaft to the output of a conventional variable speedgear box 52. The input of gear box 52 is connected through a chain 54 topreviouslymentioned motor 26.

A detailed description of the construction and operation of feedermechanism similar to that so far described herein may be found inpreviously-mentioned U.S. Reissue Patent 24,843.

Mounted on feeder 30 according to the present invention is a rotatingcam mechanism or means 56. Mechanism 56 functions to coordinate theoperate of a sheet unloader 58 (positioned adjacent the offbearing endsof the decks in the dryer) with that of feeder 30.

Considering the construction of and mounting provided for mechanism 56,and referring to FIGS. 1, 2, and 3, indicated at 60 is an elongatedshaft paralleling shaft 40. The shaft is suitably journaled as by thebearing 62 shown in FIG. 2 which is mounted on frame 32. The left end ofshaft 60 in FIG. 2 is threaded.

Secured to the right end of the shaft in FIG. 2, immediately to theright of bearing 62, is a sprocket 66. Sprocket 66 is connected to shaft40 by means of a chain 63, and this driving connection is a positive oneproducing exactly one revolution of shaft 60 for one revolution of shaft40.

Anchored to shaft 60 immediately to the left of bearing 62 in FIG. 2 isa spacer 70, and next to this spacer is an annular friction pad oragency 72. Pad 72 is made of a suitable high-friction material such asasbestos.

Cam mechanism 56, which is positioned to the left of pad 72 in FIG. 2,comprises a pair of cam elements 74 ,76 mounted with shaft 60 extendingloosely through their centers. The cam elements have substantially thesame side profiles, and include radially projecting nodes 74a, 76a andarcuate slots 74b, 76b. The cam elements are locked together formovement as a unit by means of a nut and bolt assembly, or releasablelocking means, 78 received in slots 74]), 7611. As can be seen in FIG. 3Where the cam elements are shown from the side, nodes 74a, 76a overlapone another. By releasing assembly 78, it will be apparent that theelements may readily be rotated relative to each other, to change thedegree of overlap of the nodes. Slots 74b, 76b function as limit meanslimiting the amount of relative angular adjustment permitted between theelements. Thus, for all adjusted positions of the elements, and withassembly 78 locking the elements together, the nodes always overlap oneanother.

Cam element 74 is suitably secured to the right end of a sleeve 8%) inFIG. 2, which is freely received on shaft 60. The left end of the sleevecarries a knurled knob 82. Screwed onto the threaded left end of shaft60 in FIG. 2 is an internally threaded nut 84 with knob 86 attached.Knob 86 and pad 72 constitute a releasable clamping mechanism hereinfor, on turning of knob 86 to advance nut 84 inwardly on shaft 60,sleeve 30 is clamped against pad 72 to secure the cam elements in agiven position on shaft 60. With loosening of nut 84, the cam elementsmay be shifted angularly on shaft 60 to a new position by turning ofknob 82.

Also mounted on freeder 30 are five switch assemblies 88, 9t), 82, 94,96 with the number of such switch assem blies corresponding to thenumber of decks in dryer 10. The switch assemblies are distributedcircumferentially about the cam mechanism. The assemblies aresubstantially the same in construction, and considering assembly 83(which is illustrated in some detail in FIGS. 2 and 3), it includes aswingable arm 88a ganged to an electrical switch or control device shownin dashed outline at 88b (FIG. 3). Arm 88a carries a roller 89 on itsouter end,

The arm is biased by a concealed spring in the assembly to the positionshown in dash-dot outline in FIG. 3. On rotation of cam mechanism 56,roller 83 is engaged by nodes 74a, 7 6a to swing the arm to one side, asillustrated by the solid outline position of the arm in FIG. 3. With thearm in its first-mentioned position, switch 88b is in an open ornonactuating state. With the arm swung to one side, and roller 89 alongthe radially outermost surfaces of nodes 74a, 76a, switch 88b is in aclosed or actuating state. It will be apparent that the length of timethat switch 88b remains closed depends upon the length of time thatroller 8-9 rides on the outer surfaces of the nodes, and this time, inturn, depends upon the degree of overlap of the nodes. With cammechanism 56 rotating, the nodes therein swing the arms in the variousswitching assemblies in the following order: 96, 94, 92, 90, 88, andthen back to 96.

According to the invention, switch assemblies 88, 90, 92, 94, 96function, with their respective switches closed successively by the cammechanism, to energize different discharging mechanisms provided inunloader 58 for discharging onto an oifbearing conveyor 97 sheets thatarrive from the various decks in the dryer. In FIG. 1, such mechanismsfor discharging sheets coming from decks 12, 14, 16, 18, 20 arerepresented by the blocks at 98, 100, 12, 104, 106, respectively.

Because the various decks in dryer operate at the same speed, sheets fedsequentially to the difierent dryer decks during each feed cycle offeeder 30 emerge from the offbearing ends of the decks at a later timein the same sequence. Thus, for proper coordinated operation of theunloader, and with the unloader receiving sheets in the sequence justmentioned, it is important that the respective discharging mechanismsassociated with the different dryer decks also operate in the samesequence.

Discharging mechanisms 98, 100, 102, 104, 106 are connected electricallyto the switches in switch assemblies 88, 90, 92, 94, 96, respectively,by means of conductors 110, 112, 114, 116, 118, junction box 120, 122,cable 124, and conductors 110a, 114a, 116a and 118a.

Describing now the construction of unloader 58, and referringparticularly to FIGS. 4 and 5, the unloader includes a frame 126disposed in front of the offbearing end of the dryer, and a receivingstation (shown in FIG. 4 at 128, 130, 132, 134, 136) for each deck inthe dryer. In general terms, each receiving station comprises a shortconveyor section operable to transport veneer sheets along a path whichis a longitudial extension of the path of travel of sheets through thedryer defined by the dryer deck feeding the conveyor means. Sheetsreceived on a conveyor section are brought to rest with their endsaligned, and at a time thereafter, as determined by previously-mentionedcam mechanism 56, a discharging mechanism in the unloader operates toshift the sheets forwardly onto offbearing conveyor 97.

Considering structural details of the unloader, frame 126 comprises aseries of uprights 138. Fastened to these uprights, on either side ofthe frame, is a series of longitudinally extending supports 140, with apair of such supports provided in each receiving station for theconveyor means in the station.

Considering station 136, journaled on frame 126 by means of bearings,such as bearing 142 fastened to supports 140, and adjacent the infeedend of the unloader, is a transversely-extending roller 144. Roller 144is a smoothsurfaced, nonpowered roller which functions to guide the endsof sheets traveling into the unloader, and to support the sheets whilethe same are pushed forwardly by dryer deck 20. Sheets emerging from thedryer are deflected so that they come into contact with roller 144 bymeans of a guide element 146 mounted on the infeed end of frame 126.

Directly in front of roller 144 is a pair of smooth-surfaced unloadingrollers 148, 150 journaled on frame 126 by means of bearings 152anchored to supports 140. Secured to one set of ends of rolls 148, 150are sprockets 154, 156 which are used, as will be described, forrotating the rollers under power.

Superimposed over roller 150 is a roller 158. This roller has endsjournaled on arms 160 that are pivoted at 162 through brackets 164 onsupports 140. Roller 158 is urged 6 by gravity against roller 150, andfunctions to press veneer sheets that travel thereunder down onto rollerbeneath it. Roller 158 may be provided with a yieldable outer covering,such as the rubber covering indicated at 166 in FIG. 5, wherebyrelatively even pressure is exerted by the roller downwardly on sheetstraveling thereunder.

Under normal operating conditions, rollers 148, 150 (and roller 158which is driven by roller 150) are rotated at a considerably fasterspeed than the rollers in the dryer. Thus, when veneer sheets engagethese rollers, they are withdrawn from the dryer with the sheetstraveling at a considerably greater speed than their travel speedthrough the dryer. Such speeding up of the withdrawn sheets produces aspacing between sucessive charges of sheets coming from a deck, andgives time to permit proper end alignment of the sheets before they aredischarged onto conveyor 97.

Toward the offbearing end of the unloader from the rollers justdescribed are smooth-surfaced, nonpowered rollers 168, 170 journaled onthe frame of the unloader in bearing 172, 174, respectively. Thefunction of these rollers is primarily to guide ends of sheets as suchare shifted forwardly by rollers 150, 158. Directly adjacent theotfbearing end of the unloader is previously-mentioned dischargingmechanism 106 for station 136. Mechanism 106 includes a braking roller178 for supporting the bottom faces of sheets advanced thereover,journaled in bearings 180 secured to supports 140. As can be seen inFIG. 5, the cylindrical surface of roller 178 is surrounded by a highcoefiicient of friction covering, such as rubber covering 182.

According to the invention, roller 178 is driven intermittently, asdetermined by cam mechanism 56, by means of an electric drive motor 184mounted on frame 126. Motor 184 is drivingly connected to roller 178 bymeans of a drive chain 186. Chain 186 is trained. over a sprocket 188secured to one end of roller 178, a motor-driven sprocket 190 (FIG. 5),and an idler sprocket 192. Motor 184 is operated upon energizing of amotor-starting solenoid, indicated in block form at 194 which, togetherwith the motor, also comprises part of discharging mechanism 106.

When motor 184 is running, roller 178 is rotated to cause veneer sheetssupported thereon to shift to the left in FIG. 4, with such sheets beingdirected onto offbearing conveyor 97. When the motor is not running,roller 178 is stationary, and the outer surface of covering 182constitutes a braking surface that slows down, and then stops, sheetstraveling thereover. The braking force exerted by covering 182 on sheetsis such that all sheets in a charge come to rest with their forwardedges substantially aligned.

Station 136 also includes a roller 196 journaled on the frame anddisposed above idler roller 168. This roller functions to support thetrailing ends of sheets prior to operation of roller 178 to transfersuch sheets away from the unloader.

The conveyor means in receiving stations 128, 130, 132, and 134 aresimilar in construction to the conveyor means just described, and thedischarging mechanism in these other conveyor means are substantiallythe same in construction as discharging mechanism 106. Thus, mechanisms98, 100, 102, 104, have rollers 198, 200, 202, 204, respectively,corresponding to roller 178, drive motors, 206, 208, 210, 212,respectively, corresponding to motor 184, and motor-starting solenoids214, 216, 218, 220, corresponding to solenoid 194.

As mentioned earlier, the unloading rollers in the various conveyormeans, corresponding to rollers 148', 150, are rotated under power.Ordinarily, these rollers are rotated constantly by means which will nowbe described. Referring to (FIG. 4, mounted on frame 126 beneathreceiving station 136 is an electric motor 222 connected to a drivesprocket 224. Trained over the drive sprocket and sprockets such assprockets 154, 156 secured to rollers 7 14-8, 150, is a drive chain 226.Also training the drive chain are idler sprockets 228, 230, 232, 234.With motor 222 running, the various unloading rollers are drivensimultaneously in the same direction to transport sheets from the rightto the left in FIG. 4.

Completing now a description of the electrical connections providedbetween the switch assemblies mounted on feeder 30 and the dischargingmechanisms in unloaded 58, FIG. 6 illustrates such connections.Indicated at 236, 238 are .a pair of main power supply conductorsconnected to a suitable source of AC power. Conductor 236 is connectedthrough a switch 240 to an elongated conductor 242 which is connected byappropriate jumpers to one set of contacts in switches 88b, 90b, 92b,94b and 96b of the switch assemblies. Conductor 238 is connected througha switch 244- (ganged to switch 240) to an elongated conductor 246 whichis connected to one set of ends of the coils in motor-starting relays214, 216, 218, 220 and 194. The opposite set of ends of such coils areconnected, respectively, through conductors 110, 112, 114, 116, 118 tothe other set of contacts in switches 88!), 90b, 92b, 94b and 96b.

Connected in series between conductors 2'42, 246 is a switch 248, andthe coil 250a of a relay 250. Relay 250 also includes normally openswitches 250k through 250 which are connected in series, respectively,between condoctors 110, 112, 114, 116, 118, and conductor 242.

Shown at 252, 254 is another pair of power supply conductors alsoconnected to a suitable source of AC power. Conductors 252, 254 areconnected through ganged-together switches 256, 258, respectively, toconductors 260, 262, respectively. Conductor 260 is connected to one setof input terminals in drive motors 206, 208, 210, 212, 184. The otherinput terminals in these motors are connected through the normally openswitches 214a, 216a, 218a, 220a and 194a of their associated startingsolenoids to conductor 262. Thus, each drive motor is connected inseries between conductors 260, 262 through the switch in its associatedmotor-starting solenoid.

Explaining briefly the operation of the circuit in FIG. 6, to place thecircuit in an operative condition, switches 240, 244, 256, 268 areclosed. Normally, switch 248 is left open whereby coil 250a isnon-energized, and switches 25011450 are open. The length of time thateach switch is held closed depends upon the length of time that theroller on the arm connected to the switch rides on the outer surfaces ofthe nodes in the cam mechanism.

When one of the switches, for example switch 96b closes, power is thensupplied to energize the coil in its associated motor-starting solenoid194, and switch 194a closes. Upon closing of switch 194a, power issupplied to operate drive motor 184 in discharging mechanism 106,whereupon sheets that are at rest upon roller 178 are shifted out of theunloader and onto conveyor 97. Motor 184- continues to operate so longas the coil in solenoid 194 is energized, and this depends upon thelength of time that the roller on the arm in switching device 96 ridesupon the outer surfaces of the nodes in the cam mechanism. A similaroperation takes place in the other discharging mechanism with closing ofthe other switches distributed about mechanism 56.

When it is desired to clear simultaneously all sheets held in theunloader, independently of the action of cam mechanism 56, switch 248 isclosed to energize relay coil 250a. With energizing of this coil,switches 250b-250f close to supply power to the coils in all of themotorstarting relays in the discharging mechanisms.

Describing now how the apparatus shown herein performs as a whole, andexplaining how the operation of unloader 58 is coordinated according tothe invention with the operation of feeder 30, initially, certainadjustments are made in cam mechanism 56. More specifically, with knob86 loosened on shaft 60, and assembly 78 also loosened, cam elements'74, 76 are rotated relative to one another to produce proper offset anda given degree of overlap in nodes 7 4a, 76a. Thus, with the length ofsheets to be processed known, the nodes are offset sufficiently toproduce drive motor operating periods which will insure completedischarge of each charge of sheets from the unloader. The oifsetselected is not so great as to cause two discharging mechanisms tooperate at once. Assembly '78 is then tightened to fasten the two camelements together for operation as a unit.

Next, through manipulation of knob 82 and sleeve 80, the cam mechanismis adjusted to have the proper angular position on shaft 60. Moreparticularly, the cam mechanism is positioned on the shaft whereby, withmotor 26 powering the dryer decks and turning shafts 40, 60, and withmotor 222 driving the various unloading rollers in the unloader, thenodes in the cam mechanism close switches 88b, 90b, 92b, 94b, 96bsuccessively at the proper time to produce appropriate clearing by thedischarging mechanisms. After such an adjustment, knob 86 is turned toclamp mechanism 56, sleeve 80, and knob 82 between washer 72 and nut 84to secure the cam mechanism for rotation with shaft 60.

With cam mechanism 56 properly adjusted, on each rotation of shaft 40whereby one cycle of the feeder is performed, one complete cycle ofunloading by the unloader results. For each charge in a cycle that isfed into the dryer, another charge is unloaded. The relationship is apositive one, by reason of the positive drive connection between shaft40 and cam mechanism 56. Adjustable cam mechanism 56 permits adjustmentsreadily to be made whereby the timing desired for a particular operationis obtained.

Such coordination obviously results in a highly efficient flow of sheetsthrough the dryer and unloader. It will be appreciated that an importantcontributing feature and advantage herein is that the cam mechanismincludes novel relatively rotatable cam elements having nodes that canbe adjusted to different overlapping positions. With such adjustmentpossible, the lengths of the operating periods for the dischargingmechanisms can easily be varied to accommodate sheets having differentlengths. Thus, the mechanisms can always be operated for just the rightamounts of time, and power is conserved. In addition, such a provisionis useful in adjusting the configuration of the cam mechanism to avoidthe possibility of more than one motor-actuating switch being closed ata time.

Further, with the angular position of the cam mechanism on shaft 60being adjustable, and with means provided for clamping the mechanism inplace when properly adjusted, it is a relatively simple matter toposition the cam mechanism whereby the various discharging mechanismsoperate at the proper times. Once the cam mechanism is clamped in placefor rotation with the shaft, and with the switches that are associatedwith the discharging mechanisms properly distributed about and adjacentthe cam mechanism, the discharging mechanisms are then operatedcompletely automatically and in appropriate succession. Accordingly, andbecause feeding and discharging of sheets takes place at the same rate,and in directly corresponding sequences, the dryer is always properlyfilled with sheets, and there is no problem of sheets stacking up in theunloader.

While a preferred embodiment of the invention has been described herein,it is appreciated that variations and modifications may be made withoutdeparting from the spirit of the invention. For example, an unloaderaccording to the invention may easily be provided which will accommodatemore or less than five conveyor decks, with appropriate cam mechanismand switches also provided to coordinate the operation of thedischarging mechanisms in such an unloader.

It is claimed and desired to secure by Letters Patent:

1. In sheet-handling apparatus including a multiple deck conveyer and afeeder with means operable in a feed cycle to feed successive charges ofsheets onto the infeed ends of different decks in said multiple deckconveyer, and an unloader comprising, for each deck, anintermittently-operated discharging mechanism for removing sheets fromthe off-bearing end of the deck,

a control device controlling each discharging mechanism having a firststate that it occupies when the discharging mechanism is not operating,and a second state that it occupies when the discharging mechanism isoperating,

said control devices for the various discharging mechanisms beingpositioned adjacent one another in a continuous path, and

rotating cam means operatively connected to and positively driven bysaid feeder for revolving through a predetermined angular distanceduring a feed cycle of the feeder,

said cam means on being rotated engaging successive devices in said pathduring each feed cycle to place such successive devices in their saidsecond states,

said cam means comprising a pair of cam elements mounted adjacent eachother and relatively adjustable by relative angular displacement about acommon axis, said cam elements including nodes adjacent theircircumferences which collectively form a continuous node surface whichis adjustable in length by relative angular displacement of the camelements, such adjustment changing the time that the cam means engages agiven device on rotation of the cam means.

2. The apparatus of claim 1, wherein said cam means further comprisesreleasable locking means releasably locking said cam elements in a givenadjusted position.

3. The apparatus of claim 2, wherein said cam means further comprisesmeans limiting the amount of relative angular adjustment permittedbetween the elements.

4. The apparatus of claim 1, wherein said cam means is operativelyconnected to said feeder by means comprising a shaft supporting said camelements with the elements being rotatable on the shaft for adjustmentpurposes, and releasable clamping means operatively interposed betweensaid shaft and elements releasably clamping the elements in place forturning with the shaft.

5. The apparatus of claim 4, wherein said releasable clamping meanscomprises a friction agent interposed between one cam element and saidshaft, and means adjustable to force said cam element toward saidfriction agency.

References Cited UNITED STATES PATENTS 2,693,595 11/1954 Belluche et al1-106 3,280,960 10/1966 Gordon 198-32 3,285,436 11/1966 Inuzuka et al21416.1 3,301,377 1/1967 Larson 198-32 GERALD M. FORLENZA, PrimaryExaminer. R. B. JOHNSON, Assistant Examiner.

US. Cl. X.R. 198-20, 32

